An exemplary conventional fuel cell system is operated based on an operation plan designed to surely actuate a fuel cell for durable years which are expected by users. For example, Patent Literature 1 discloses a fuel cell system in which to enable a power generation operation for a time period longer than durable years (e.g., 10 years) of the fuel cell which are expected by the users, an allowable operation time per predetermined period is planned based on a total durable operation time (e.g., about 40000 h) of the fuel cell and the fuel cell is operated based on the operation plan (e.g., see Patent Literature 1).
FIG. 11 is a schematic view showing a configuration of the conventional fuel cell system disclosed in Patent Literature 1. In this fuel cell system, a controller 50 creates an operation plan of a fuel cell 15 in such a manner that an allowable operation time of the fuel cell 15 is set based on a past actual operation performance stored in a data storage means. The operation of the fuel cell 15 is initiated based on this operation plan. Then, after a passage of a predetermined unit time, an actual operation time is compared to an allowable operation time, and a difference value between the actual operation time and the allowable operation time is calculated if the actual operation time is less than the allowable operation time. Then, the operation plan already created is updated into a new operation plan which is a sum of the difference value and an allowable operation time in a next time.